Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
nang noi » nang doc
va triet » va thiet, ve triet, cua triet
nang doi » nang doc, hang doi, nang dong
va trien » va truyen, va thiet, va tuyen
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
lang xa » lang ha, dang xay, lang van
sach o » sach lo, sac o, sach y
o lang » hoa lang, hoi lang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach o lang xa hoi. hieu va cac tuc xa ((nang doi) or (nang noi)) ((va triet) or (va trien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach o lang xa hoi. hieu va cac tuc xa ((nang doi) OR (nang noi)) ((va triet) OR (va trien)).
• Adding a wildcard symbol may retrieve word variants: thu sach o lang xa hoi. hieu va cac tuc xa ((nang doi) or (nang noi)) ((va triet) or (va trien))*.